1. Field of the Invention
The present invention is directed to a binder assembly or the like, the term "binder assembly" as used herein being employed in a broad context to encompass conventional notebook type binders as well as other types of tabulating systems having removable retaining leaves, such as index card holders, etc.
2. The Prior Art
Conventional binder assemblies, such as looseleaf binders, are comprised of a backing member or spine, to which is movably mounted a leaf holder mechanism typically in the form of a split ring or the equivalent. In the closed or leaf carrying position, the component or components defining the ring provide a closed loop or series of loops which pass through an aperture or apertures of the leaves. In order to remove a given leaf, the holder mechanism is actuated so as to split the loop, whereby any of the leaf or leaves adjacent the open ends of the loop may be removed.
If it is desired to remove a given leaf, typical practice requires that the leaf to be removed be disposed uppermost, the rings opened and the leaf extracted. This procedure is readily effected where there are relatively few leaves mounted in the binder and it is thus possible to align the leaf to be removed with the split of the ring.
However, where a large quantity of leaves are mounted in the binder it may be impossible to align a particular leaf which is desired to be removed with the opening between the split rings. Under such circumstances removal of the leaf in question requires that a multiplicity of intervening leaves be first removed.
This procedure is time consuming and, in addition, the remounting of the multiple leaves necessarily removed is a cumbersome task since the apertures in the mass of leaves to be replaced must first be mutually aligned before remounting.
Conventional split ring type binders are further disadvantageous in that the snap mechanism may frequently fail. Also, the distal ends of the rings in the closed position frequently do not provide a smooth interfit or transition, with the result that when leaves are shifted across the transition, increments of the paper adjacent the mounting apertures are sawed or worn away.
In a further conventional type of tabulating device frequently used for holding index cards, the cards are punched with non-reentrant configurations. The holder mechanism includes complementally shaped bars or rods, the cards being mounted be deforming or flexing the cards to permit the rods to enter the apertures of the cards.
Tabulating devices of this sort are disadvantageous where a card must be periodically removed and replaced since with each mounting and demounting the material of the card is flexed and its connection to the holder thus rendered less secure.